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<div class="titlepage"><div><div><h3 class="title">
<a name="asio.reference.CompletionHandler"></a><a class="link" href="CompletionHandler.html" title="Completion handler requirements">Completion handler
      requirements</a>
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<p>
        A completion handler must meet the requirements for a <a class="link" href="Handler.html" title="Handlers">handler</a>.
        A value <code class="computeroutput">h</code> of a completion handler class should work correctly
        in the expression <code class="computeroutput">h()</code>.
      </p>
<h5>
<a name="asio.reference.CompletionHandler.h0"></a>
        <span><a name="asio.reference.CompletionHandler.examples"></a></span><a class="link" href="CompletionHandler.html#asio.reference.CompletionHandler.examples">Examples</a>
      </h5>
<p>
        A free function as a completion handler:
      </p>
<pre class="programlisting">void completion_handler()
{
  ...
}
</pre>
<p>
        A completion handler function object:
      </p>
<pre class="programlisting">struct completion_handler
{
  ...
  void operator()()
  {
    ...
  }
  ...
};
</pre>
<p>
        A lambda as a completion handler:
      </p>
<pre class="programlisting">my_io_service.post(
    []()
    {
      ...
    });
</pre>
<p>
        A non-static class member function adapted to a completion handler using
        <code class="computeroutput">std::bind()</code>:
      </p>
<pre class="programlisting">void my_class::completion_handler()
{
  ...
}
...
my_io_service.post(std::bind(&amp;my_class::completion_handler, this));
</pre>
<p>
        A non-static class member function adapted to a completion handler using
        <code class="computeroutput">boost::bind()</code>:
      </p>
<pre class="programlisting">void my_class::completion_handler()
{
  ...
}
...
my_io_service.post(boost::bind(&amp;my_class::completion_handler, this));
</pre>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2018 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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